DoorCounter

The Android tool works perfectly fine without a permanent Internet connection, does not ask for intrusive permissions, and stores all the information it collects in the local memory. It aims to be a reliable assistant for gatekeepers, security officers, and other categories of employees who control access to a building or location. 
 
Users do not have to register or configure sophisticated settings after installing the app. For starters, they must add a maximum limit of people who can be inside that location at the same time and then specify the number of persons who are already in there. Once the counting begins, users must tap the plus or minus button each time a person enters or leaves the building. There is no risk of exceeding the maximum number without realizing it because a warning is going to show up on the screen when they get close to the upper limit. 
 
Apart from counting, users can explore a graph that shows which are the busiest and least crowded times of the day. Furthermore, they get the chance to find out when the last customer came in and the average number of people inside. 
 
In conclusion, DoorCounter is a perfect solution for shopping malls, grocery stores, supermarkets, and other economic operators that can grant access to a limited number of persons in their buildings.